Occupational injury represents an important health and economic problem in agriculture. There is a substantial body of literature on injury experience among farmers and agricultural workers in different geographical regions of the United States. However, to date, no single study has focused on occupational injury among migrant and seasonal farmworkers. In California alone, estimates of this population range from 600,000 to 1.2 million, in comparison to the national estimate of 3 million. This population typically comprises of ethnic and linguistic minorities. The predominant ethnic group is Hispanic, and in California this group constitutes approximately 90( of migrant and seasonal farmworkers. Factors such as low educational status, poor English and literacy skills, and inadequate understanding of existing reporting and support structures such as Workers Compensation may potentially contribute towards increased injury risk in this population. An uniqueness of the current study is its focus on this large, yet understudied at-risk population. This research proposes a prospective cohort study of occupational injury among migrant Hispanic farmworker families through a harvest season. Specifically, the cohort will comprise of 500 farmworker families residing in 6 Migrant Housing Centers, geographically proximal to Davis, California. It is expected that the cohort will include approximately 1000 adults and 1000 dependent children. This will allow the investigators to address specific hypotheses regarding remediable risk factors for injury that have not been evaluated in other populations. Such factors include organophosphate pesticide exposure (as indicated by erythrocyte acetylcholinesterase levels), piece-work versus hourly pay, language appropriate safety training, and the role of multiple employment. Data and results established from this study will be useful for targeting and designing injury reduction programs in this population.